Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 317

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

JAEA Reports

Status of study of long-term assessment of transport of radioactive contaminants in the environment of Fukushima (FY2018) (Translated document)

Nagao, Fumiya; Niizato, Tadafumi; Sasaki, Yoshito; Ito, Satomi; Watanabe, Takayoshi; Dohi, Terumi; Nakanishi, Takahiro; Sakuma, Kazuyuki; Hagiwara, Hiroki; Funaki, Hironori; et al.

JAEA-Research 2020-007, 249 Pages, 2020/10

JAEA-Research-2020-007.pdf:15.83MB

The accident of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. occurred due to the Great East Japan Earthquake, Sanriku offshore earthquake, of 9.0 magnitude and the accompanying tsunami. As a result, large amount of radioactive materials was released into the environment. Under these circumstances, Japan Atomic Energy Agency (JAEA) has been conducting "Long-term Assessment of Transport of Radioactive Contaminants in the Environment of Fukushima" concerning radioactive materials released in environment, especially migration behavior of radioactive cesium since November 2012. This report is a summary of the research results that have been obtained in environmental dynamics research conducted by JAEA in Fukushima Prefecture.

JAEA Reports

Status of study of long-term assessment of transport of radioactive contaminants in the environment of Fukushima (FY2018)

Nagao, Fumiya; Niizato, Tadafumi; Sasaki, Yoshito; Ito, Satomi; Watanabe, Takayoshi; Dohi, Terumi; Nakanishi, Takahiro; Sakuma, Kazuyuki; Hagiwara, Hiroki; Funaki, Hironori; et al.

JAEA-Research 2019-002, 235 Pages, 2019/08

JAEA-Research-2019-002.pdf:21.04MB

The accident of the Fukushima Daiichi Nuclear Power Station (hereinafter referred to 1F), Tokyo Electric Power Company Holdings, Inc. occurred due to the Great East Japan Earthquake, Sanriku offshore earthquake, of 9.0 magnitude and the accompanying tsunami. As a result, large amount of radioactive materials was released into the environment. Under these circumstances, JAEA has been conducting Long-term Environmental Dynamics Research concerning radioactive materials released in environment, especially migration behavior of radioactive cesium since November 2012. This report is a summary of the research results that have been obtained in environmental dynamics research conducted by JAEA in Fukushima Prefecture.

Journal Articles

Superconductivity in repulsively interacting fermions on a diamond chain; Flat-band-induced pairing

Kobayashi, Keita*; Okumura, Masahiko; Yamada, Susumu; Machida, Masahiko; Aoki, Hideo*

Physical Review B, 94(21), p.214501_1 - 214501_7, 2016/12

 Times Cited Count:38 Percentile:88.59(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Evaluation of beam phase restriction with beam phase defining slit in the JAEA AVF cyclotron

Miyawaki, Nobumasa; Fukuda, Mitsuhiro*; Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.706 - 708, 2015/09

no abstracts in English

Journal Articles

Preliminary test of injection tuning using an emittance and acceptance measurement system at the JAEA AVF cyclotron

Kashiwagi, Hirotsugu; Miyawaki, Nobumasa; Kurashima, Satoshi; Okumura, Susumu

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.703 - 705, 2015/09

no abstracts in English

Journal Articles

Present status of TIARA at JAEA

Yuyama, Takahiro; Ishibori, Ikuo; Kurashima, Satoshi; Yoshida, Kenichi; Ishizaka, Tomohisa; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Usui, Aya; Miyawaki, Nobumasa; et al.

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.302 - 304, 2015/09

no abstracts in English

Journal Articles

Enhancement of beam pulse controllability for a single-pulse formation system of a cyclotron

Kurashima, Satoshi; Miyawaki, Nobumasa; Kashiwagi, Hirotsugu; Okumura, Susumu; Taguchi, Mitsumasa; Fukuda, Mitsuhiro*

Review of Scientific Instruments, 86(7), p.073311_1 - 073311_8, 2015/07

 Times Cited Count:10 Percentile:50.74(Instruments & Instrumentation)

The single-pulse formation technique using a beam chopping system consisting of two types of high-voltage beam kickers was modified to improve the quality and intensity of the single-pulse beam with pulse intervals over 1 $$mu$$s at TIARA cyclotron facility of Japan Atomic Energy Agency. Reduction of the multi-turn extraction number for suppressing the neighboring beam bunch contamination was achieved by restriction of a beam phase width and precise optimization of a particle acceleration phase. In addition, the single-pulse beam intensity was increased by a factor of two or more by a combination of two types of beam bunchers using sinusoidal and saw-tooth voltage waveforms. As a result, a contamination rate of neighboring beam bunches in the single-pulse beam was reduced to less than 0.1 %. Long-term purification of the single pulse beam was guaranteed by the well-controlled magnetic field stabilization system for the TIARA cyclotron magnet. Provision of the high quality intense single-pulse beam contributes to improve the accuracy of experiments for investigation of scintillation light time-profile and for neutron energy measurement by a time-of-flight method.

Journal Articles

Formation of a uniform ion beam based on nonlinear focusing and its applications at the JAEA TIARA cyclotron

Yuri, Yosuke; Yuyama, Takahiro; Ishizaka, Tomohisa; Yoshida, Kenichi; Ishibori, Ikuo; Okumura, Susumu

Proceedings of 6th International Particle Accelerator Conference (IPAC '15) (Internet), p.236 - 238, 2015/06

Journal Articles

Mathematical Modeling of Radioactive Contaminants in the Fukushima Environment

Kitamura, Akihiro; Kurikami, Hiroshi; Yamaguchi, Masaaki; Oda, Yoshihiro; Saito, Tatsuo; Kato, Tomoko; Niizato, Tadafumi; Iijima, Kazuki; Sato, Haruo; Yui, Mikazu; et al.

Nuclear Science and Engineering, 179(1), p.104 - 118, 2015/01

 Times Cited Count:8 Percentile:65.81(Nuclear Science & Technology)

The prediction of the distribution and fate of radioactive materials eventually deposited at surface in the Fukushima area is one of the main objectives and expected to be achieved in an efficient manner. In order to make such prediction, a number of mathematical models of radioactive contaminants, with particular attention on cesium, on the land and in rivers, lakes, and estuaries in the Fukushima area are developed. Simulation results are examined with the field investigations simultaneously implemented. The basic studies of the adsorption/absorption mechanism of cesium and soils have been performed to shed light on estimating distribution coefficient between dissolved contaminant and particulate contaminant.

Journal Articles

Evaluation of phase bunching in the central region of a cyclotron by a radial probe with a plastic scintillator

Miyawaki, Nobumasa; Fukuda, Mitsuhiro*; Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu; Arakawa, Kazuo*; Kamiya, Tomihiro

Nuclear Instruments and Methods in Physics Research A, 767, p.372 - 378, 2014/12

 Times Cited Count:3 Percentile:30.04(Instruments & Instrumentation)

Journal Articles

Technical development for the utilization of large-area uniform ion beams at the JAEA TIARA cyclotron

Yuri, Yosuke; Yuyama, Takahiro; Ishizaka, Tomohisa; Ishibori, Ikuo; Okumura, Susumu

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.862 - 865, 2014/10

no abstracts in English

Journal Articles

Time resolution of beam phase distribution measurement system for the JAEA AVF cyclotron

Miyawaki, Nobumasa; Fukuda, Mitsuhiro*; Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu; Arakawa, Kazuo*; Kamiya, Tomihiro

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1179 - 1181, 2014/10

no abstracts in English

Journal Articles

Effective emittance expansion for transverse acceptance measurement of an AVF cyclotron

Kashiwagi, Hirotsugu; Miyawaki, Nobumasa; Kurashima, Satoshi; Okumura, Susumu

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1186 - 1188, 2014/10

no abstracts in English

JAEA Reports

Development of microbeam formation and single-ion hit technologies at the TIARA cyclotron

Yokota, Wataru; Sato, Takahiro; Kamiya, Tomihiro; Okumura, Susumu; Kurashima, Satoshi; Miyawaki, Nobumasa; Kashiwagi, Hirotsugu; Yoshida, Kenichi; Funayama, Tomoo; Sakashita, Tetsuya; et al.

JAEA-Technology 2014-018, 103 Pages, 2014/09

JAEA-Technology-2014-018.pdf:123.66MB

The world's first microbeam focusing technology for heavy ions of hundreds MeV accelerated by a cyclotron has been developed at the TIARA facility in the Takasaki Advanced Radiation Research Institute of the Japan Atomic Energy Agency. The technology enables us to form a microbeam of less than 1 $$mu$$m in diameter and to shoot a specified point on a target by one ion (single-ion hit) with spatial accuracy of microbeam size. In the course of the development, a cyclotron technology to accelerate a small energy-spread beam of hundres MeV, which is necessary for focusing to 1 $$mu$$m, has been developed as well as a beam focusing apparatus, beam size measurement and so forth based on the several-MeV microbeam/single-ion hit system of the TIARA electrostatic accelerators. Applicability of the technologies was examined by actual use in irradiation experiment and the result were fed back to them. This paper reports the process and the results of the development over ten years.

Journal Articles

Development of pulse beam formation technique for the JAEA AVF cyclotron

Kurashima, Satoshi; Miyawaki, Nobumasa; Okumura, Susumu

Hoshasen, 40(2), p.99 - 103, 2014/06

no abstracts in English

Journal Articles

Ferromagnetism in multi-orbital Fermi gas loaded on a one-dimensional optical lattice

Kobayashi, Keita; Okumura, Masahiko; Ota, Yukihiro*; Yamada, Susumu; Machida, Masahiko

JPS Conference Proceedings (Internet), 3, p.016006_1 - 016006_6, 2014/06

no abstracts in English

Journal Articles

Transformation of the beam intensity distribution and formation of a uniform ion beam by means of nonlinear focusing

Yuri, Yosuke; Yuyama, Takahiro; Ishizaka, Tomohisa; Ishibori, Ikuo; Okumura, Susumu

Plasma and Fusion Research (Internet), 9(Sp.3), p.4406106_1 - 4406106_4, 2014/06

Journal Articles

Formation of large-area heavy-ion uniform beams using multipole magnets in TIARA, JAEA

Yuri, Yosuke; Yuyama, Takahiro; Ishizaka, Tomohisa; Yoshida, Kenichi; Ishibori, Ikuo; Okumura, Susumu

Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.138 - 142, 2014/06

no abstracts in English

Journal Articles

Analysis of phase bunching in a central region of a cyclotron

Miyawaki, Nobumasa; Fukuda, Mitsuhiro*; Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu; Arakawa, Kazuo*; Kamiya, Tomihiro

Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.500 - 502, 2014/06

no abstracts in English

Journal Articles

Analysis of phase bunching in AVF cyclotron

Miyawaki, Nobumasa; Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu; Yoshida, Kenichi; Yuri, Yosuke; Yuyama, Takahiro; Ishizaka, Tomohisa; Ishibori, Ikuo; Nara, Takayuki

JAEA-Review 2013-059, JAEA Takasaki Annual Report 2012, P. 158, 2014/03

317 (Records 1-20 displayed on this page)